James, Duke of Monmouth, the adored illegitimate son of Charles II, was born in exile the very year that his grandfather was executed and the English monarchy abolished. Abducted from his mother on his father’s orders, he emerged from a childhood in the backstreets of Rotterdam to command the ballrooms of Paris, the brothels of Covent Garden and the battlefields of Flanders. Pepys described him as ‘the most skittish, leaping gallant that ever I saw, always in action, vaulting or leaping or clambering’.

Such was his appeal that when the monarchy itself came under threat, the cry was for Monmouth to succeed Charles II as King. He inspired both delight and disgust, adulation and abhorrence and, in time, love and loyalty almost beyond fathoming. Louis XIV was his mentor, Nell Gwyn his protector, D’Artagnan his lieutenant, William of Orange his confidant, John Dryden his censor and John Locke his comrade.